Biocompatibility of cross-linked hyaluronate (Gel-200) for the treatment of knee osteoarthritis

OBJECTIVE

To compare the biocompatibility and immunogenicity of two intra-articular hyaluronan formulations, Gel-200 (Gel-One(®)) and hylan G-F 20 (Synvisc(®) series).

EXPERIMENTAL DESIGN

A comparison of the biocompatibility of Gel-200 and hylan G-F 20 was made using a rat subcutaneous air pouch model and the knee joint of normal rabbits. Immunogenicity was evaluated using a homologous passive cutaneous anaphylaxis (PCA) assay in guinea pigs.

RESULTS

In the air pouch model in rats, characteristic fibrous belts formed in the subcutaneous tissue. Injection of hylan G-F 20 into the air pouch induced granulomatous nodules primarily composed of macrophages, multinucleated giant cells, and eosinophils accompanied with the test material in the center of the nodules in the fibrous belt. Furthermore, the thickness of the fibrous belt in the hylan G-F 20 group increased significantly compared to the saline group. Injection of Gel-200 into the air pouch induced neither granulomatous inflammation nor significant thickening of fibrous belt, while foamy macrophages containing the test material were observed. Intra-articular injection of hylan G-F 20 into the rabbit knee joints induced granulomatous inflammation, eosinophil infiltration, and significant increase in the number of cells in the synovial fluid, while these findings were absent in the Gel-200 group. In the immunogenicity assay, hylan G-F 20 induced a positive PCA reaction, but the Gel-200 did not.

CONCLUSION

Gel-200 showed more favorable biocompatibility and less immunogenicity compared to hylan G-F 20. Gel-200 is expected to be a single injection hyaluronan product with less safety concerns for the treatment of knee osteoarthritis (OA) pain.

Add-on effects of suplatast tosilate in bronchial asthma patients treated with inhaled corticosteroids

Th2 cytokines play an important role in the pathogenesis of asthma. In the present study, we investigated the effect of suplatast tosilate, a selective Th2 cytokine inhibitor, on asthma control, in terms of subjective symptoms and pulmonary function in patients treated with inhaled corticosteroids. Thirty-eight patients with bronchial asthma being treated with inhaled corticosteroids were given suplatast tosilate (100 mg three times daily) for 12 weeks, in a multicenter setting. During the study period, other medications were continued. Morning and evening peak expiratory flow, asthma symptoms, blood eosinophil count and serum IgE levels were monitored. Suplatast tosilate treatment was associated with a significant improvement in mean morning peak expiratory flow (from 295 L/min to 348 L/min, P < 0.01) and evening peak expiratory flow (from 313 L/min to 357 L/min, P < 0.01). The mean daily variation in peak expiratory flow was significantly reduced (from 11.6% to 7.3%, P < 0.01) by suplatast tosilate treatment. The greatest improvement in peak expiratory flow was observed in patients whose blood eosinophil counts were decreased by suplatast tosilate treatment. Treatment with suplatast tosilate improved pulmonary function in patients with bronchial asthma. Our results suggest the therapeutic effects observed may occur through suppression of eosinophilic inflammation.

COLLABORATIVE WORK TO EVALUATE TOXICITY ON MALE REPRODUCTIVE ORGANS BY REPEATED DOSE STUDIES IN RATS : 20)TESTICULAR TOXICITY OF NITROFURAZONE AFTER 2 AND 4 WEEKS

Nitrofurazone (NF) has been previously demonstrated to induce testicular toxicity with 4 weeks of oral administration in rats. In the present study, rats were administered NF to assess whether testicular toxicity becomes evident with a 2-week administration period. Male Sprague-Dawley rats were administered oral doses of NF at 50 mg/kg for 2 or 4 weeks. Another group was administered NF at 100 mg/kg for 2 weeks. The control animals received the vehicle (0.5% methylcellulose) for 4 weeks. Organ weights of the testis and epididymis were significantly decreased in all NF-administered animals, and seminiferous tubules were severely atrophied, due to a total absence of spermatids and degeneration and desquamation of spermatocytes. In the epididymis, decreased numbers of spermatozoa were evident in the ducts. In rats that were administered NF at 50 mg/kg, the changes in the epididymis in the 2-week group were less prominent than those in the 4-week group. In the testis, however, the changes were similar in both groups. Thus it was demonstrated that NF-induced testicular toxicity comparable to that observed after 4 weeks of administration is also detectable after 2 weeks.

Human neutrophil elastase degrades inter-alpha-trypsin inhibitor to liberate urinary trypsin inhibitor related proteins

Urinary trypsin inhibitor (UTI) is a physiological protease inhibitor and inter-alpha-trypsin inhibitor (ITI) is regarded as a precursor of UTI. The purpose of this study is to determine the mechanism of the UTI release from ITI. To examine this, ITI was digested by human neutrophil elastase at various concentrations, and UTI-related proteins which were of the same size as UTI were obtained. The amino acid sequence of the 15 amino acid residues at the N-terminal of UTI-related proteins, corresponded to that of UTI. The amino acid sequences of the small amount of peptides detected corresponded to those of peptides from the heavy chain1 (H1) and the heavy chain2 (H2) of ITI, suggesting that most UTI-related proteins do not combine with peptides from the H1 and H2 of ITI. It was also revealed that UTI-related proteins have several physiological activities similar to those of UTI, i.e., human trypsin inhibitory activity, human neutrophil elastase inhibitory activity, inhibition of tumor necrosis factor-alpha (TNF-alpha) production from rat macrophages and of superoxide production from rabbit leukocytes. These results demonstrated that ITI is a precursor of UTI which is digested by human neutrophil elastase to release UTI, and that its elastase inhibitory activity is derived from UTI.

Gene expression of the two heavy chains and one light chain forming the inter-alpha-trypsin-inhibitor in human tissues

Human inter-alpha-trypsin-inhibitor (ITI) is a serine proteinase inhibitor with a molecular weight of 220 kDa which consists of 3 different polypeptides. The constitutive components are 2 heavy chains (H1 and H2 chains) and 1 light chain (L chain), and its inhibitory activity is considered to be derived from this L chain. It has also been reported that this L chain is almost identical to the trypsin inhibitor (UTI) occurring in human urine. We examined the gene expression of the ITI constitutive peptides in human tissues using the reverse transcription (RT) -PCR technique. As a result, the genes of the H1 chain were found to be expressed in various tissues, particularly strongly in the liver. On the other hand, the genes of the H2 chain were found to be strongly expressed in the adrenal glands, brain, kidneys, and lungs, as well as the liver. Further, the PCR amplification product of the L chain was strongly detected not only in the liver but also in the pancreas, kidneys, lungs, stomach and testes. These results suggest the possibility that the major tissue which produces ITI is the liver, and the H chains and L chain (UTI) are produced as a component of ITI- related proteins in other tissues as well as in the liver.

Osteochondrodysplasia occurring in transgenic mice expressing interferon-gamma

In addition to various biological activities, interferon-gamma (IFN-gamma) inhibits bone resorption and collagen synthesis. We produced a transgenic mouse line expressing the murine IFN-gamma gene and protein in the bone marrow and thymus. Forty-five transgenic FVB/NCr mice, 23 days-9 months of age, were studied for anomalies in the skeletal system. The transgenic mice had short, wide, and deformed long bones. Young transgenic mice had epiphyseal plates severely thickened with zones of hypertrophy and degeneration with irregular metaphyseal borders. Cartilagenous masses were also observed in the metadiaphyseal marrow cavities. These lesions were primarily seen in long bones and ribs. Adult transgenic mice had residues of degenerated cartilagenous masses in the diaphyses. Many osteoclasts with well-developed ruffled borders were present on the metaphyseal cartilagenous masses in young transgenic mice. Adult transgenic mice had less prominent primary spongiosa with fewer osteoclasts at the metaphysis as compared with nontransgenic controls. The cortical bones of the transgenic mice were thinner and more immature compared with controls. Transgenic mice also had fractures, disruption of the epiphyseal plate, and degeneration of articular cartilage. Thus, the IFN-gamma transgenic mice developed a complex chondro-osseous lesion that was diagnosed as osteochondrodysplasia. The lesions may originate from primarily decreased matrix synthesis in bone and cartilage and also possible osteoclast-related changes caused by IFN-gamma overexpression in the bone marrow. Our IFN-gamma transgenic mouse will be a useful model to investigate the role of IFN-gamma in bone metabolism.

Bone marrow and thymus expression of interferon-gamma results in severe B-cell lineage reduction, T-cell lineage alterations, and hematopoietic progenitor deficiencies

Interferon-gamma (IFN-gamma) is an immunoregulatory lymphokine that is primarily produced by T cells and natural killer cells. It has effects on T-cell, B-cell, and macrophage differentiation and maturation. We have developed transgenic mice that express elevated levels of IFN-gamma mRNA and protein by inserting multiple copies of murine IFN-gamma genomic DNA containing an Ig lambda-chain enhancer in the first intron. The founder line carrying eight copies of this transgene has eightfold to 15-fold more IFN-gamma-producing cells in the bone marrow and spleen than do nontransgenic littermates. Transgenic mice show a pronounced reduction in B-lineage cells in the bone marrow, spleen, and lymph nodes. In addition, single positive (CD4+,CD8- and CD4-,CD8+) thymocyte numbers are increased twofold, yet the number of splenic T cells is reduced by 50%. There is also a twofold to threefold decrease in the frequency and total number of myeloid progenitors in the bone marrow. Granulomatous lesions and residual degenerating cartilaginous masses are also present in the bones of these mice. Overall, our data show that the abnormal expression of IFN-gamma in these transgenic mice results in multiple alterations in the immune system. These animals provide an important model to examine the role of IFN-gamma expression on lymphoid and myeloid differentiation and function.

The semidominant Mi(b) mutation identifies a role for the HLH domain in DNA binding in addition to its role in protein dimerization

The mouse microphthalmia (mi) locus encodes a basic helix-loop-helix-leucine zipper (bHLH-Zip) transcription factor called MITF (microphthalmia transcription factor). Mutations at mi affect the development of several different cell types, including melanocytes, mast cells, osteoclasts and pigmented epithelial cells of the eye. Here we describe the phenotypic and molecular characterization of the semidominant Microphthalmia(brwnish) (Mi(b)) mutation. We show that this mutation primarily affects melanocytes and produces retinal degeneration. The mutation is a G to A transition leading to a Gly244Glu substitution in helix 2 of the HLH dimerization domain. This location is surprising since other semidominant mi mutations characterized to date have been shown to affect DNA binding or transcriptional activation domains of MITF and act as dominant negatives, while mutations that affect MITF dimerization are inherited recessively. Gel retardation assays showed that while the mutant MITF(Mi-b) protein retains its dimerization potential, it is defective in its ability to bind DNA. Computer modeling suggested that the Gly244Glu mutation might disrupt DNA binding by interfering with productive docking of the protein dimer onto DNA. The Mi(b) mutation therefore appears to dissociate a DNA recognition function of the HLH domain from its role in protein dimerization.

Isolation and characterization of the human chromosomal gene for prostacyclin-stimulating factor

Prostacyclin-stimulating factor (PSF) is a protein which acts on vascular endothelial cells and stimulates the production of prostacyclin. Recently, we were able to purify PSF from the conditioned medium of cultured human diploid fibroblasts and clone PSF cDNA. In this study, we screened a human genomic library and isolated genomic clones to determine the structure of the human chromosomal PSF gene. By determining the nucleotide sequence and transcription initiation site of this gene, we found that it comprises 5 exons and 4 introns. Southern hybridization analysis indicated the presence of a single copy of the PSF gene per haploid set of chromosomes. The 300 bp upstream of the transcription initiation site had a very high GC content, and 7 binding sites for the transcription regulating factor Sp1 were present.

Mild osteopetrosis in the microphthalmia-oak ridge mouse. A model for intermediate autosomal recessive osteopetrosis in humans

Mutations at the mouse microphthalmia (mi) locus affect coat color, eye development, and mast cells. The original allele, mi, also shows severe osteopetrosis. Mice homozygous for the microphthalmia-Oak Ridge (Mior) mutation are white, microphthalmic animals with retarded incisor development. To investigate whether this mutation causes osteopetrosis, we examined skeletal tissues of the Mior mouse. A typical osteopetrotic lesion, accumulation of unresorbed primary spongiosa, was found at the metaphyses of long bones and at the costochondral junctions in Mior/Mior mice from 10 days to 37 days of age, whereas no accumulation was seen at the mid-diaphyses in these bones. The osteopetrotic conditions of Mior/Mior mice increased progressively during the first 5 weeks after birth. However, adult Mior/Mior mice 3 months or older showed improvement of the osteopetrotic condition, although the disease was not completely resolved. Ultrastructurally, osteoclasts of Mior/Mior mice had well developed ruffled borders. These results show that the Mior mutation has milder osteopetrotic changes than the original mi mutation, a surprising observation given that both mutations affect the same functional domain of the mi protein, a basic-Helix-Loop-Helix-Zipper transcription factor. The Mior phenotype resembles the intermediate autosomal recessive osteopetrosis in humans.

Intramembranous and endochondral bone changes induced by a new bisphosphonate (YM175) in the beagle dog

Oral treatment with a new bisphosphonate, YM175, for 13 wk resulted in increased bone tissue mass by both intramembranous and endochondral ossification processes in adult beagle dogs. Intramedullary bone formation due to intramembranous process was observed in dogs treated with a highly toxic dose of YM175. The newly formed woven bone trabeculae, showing immature to relatively mature figures, were present between the preexisting cancellous bone. The immature bone consisted of spindle-shaped mesenchymal cells with osteoid tissues. Many active osteoblasts surrounded the immature woven bone, while only few osteoclasts were seen on the surfaces of the new bone. Endochondral bone change was observed at the costochondral junction in all YM175-treated groups. Accumulation of unresorbed mineralized cartilage with its covering of bone at this site resulted in an increase in length of the area of primary spongiosa. Although the endochondral bone change induced by YM175 was due to a bisphosphonate-induced inhibitory effect on bone resorption, the intramedullary bone formation is unique to YM175.

Induction mechanism of human blood CD8+ T cell proliferation and cytotoxicity by natural killer cell stimulatory factor (interleukin-12)

Natural killer cell stimulatory factor (NKSF/IL-12) has been found to induce cytotoxic activity of human blood T cells. In the present study, the effect of NKSF on induction of cytotoxic CD8+ T cells in the presence or absence of monocytes was examined. Highly purified lymphocytes (> 99%) and monocytes (> 90%) were isolated by centrifugal elutriation from peripheral blood of normal donors. Then, CD8+ cells were isolated with antibody-bound magnetic beads from purified lymphocytes. The cytotoxicity of CD8+ cells was measured by 51Cr release assay for 4 h. NKSF enhanced the proliferative response of CD8+ cells stimulated with suboptimal concentrations of interleukin-2 (IL-2), but rather inhibited their proliferative and cytotoxic responses on stimulation with an optimal concentration of IL-2. NKSF stimulated CD8+ cells to produce interferon gamma (IFN gamma) irrespective of the presence of added IL-2, and this effect was augmented by co-cultivation with monocytes. Blood monocytes upregulated induction of cytotoxic CD8+ cells stimulated with NKSF alone, and this effect was abolished by addition of antibody against IFN gamma, but not of antibody against tumor necrosis factor alpha. Induction of NKSF-inducible cytotoxic CD8+ cells was inhibited by addition of transforming growth factor beta, but not of IL-4. These observations suggest that in situ induction of NKSF-stimulated cytotoxic CD8+ cells may be regulated by complex cytokine networks, depending on the participation of monocytes.

Design of variants of the second domain of urinary trypsin inhibitor (R-020) with increased factor Xa inhibitory activity

The second domain (R-020) of human urinary trypsin inhibitor (UTI) exerts similar inhibitory activities on trypsin, alpha-chymotrypsin, leukocyte elastase, and plasmin to those of UTI itself, and additionally inhibits coagulation factor Xa (FXa) and plasma kallikrein, on both of which UTI has no inhibitory effect. In the present study, we attempted to increase this FXa-inhibitory activity by modeling the structure of R-020-FXa complex and substituting one or two amino acids in R-020 using recombinant DNA technology. Molecular modeling of R-020 and FXa was performed with reference to X-ray analysis of the complex of bovine pancreatic trypsin inhibitor (BPTI) and bovine trypsin to determine the site of amino acid modification. The expression plasmids into which R-020 genes with base substitution were inserted were prepared and introduced into Escherichia coli to express R-020 variants. The resulting variants were purified and their enzyme inhibitory activities were measured. The FXa-inhibitory activity was increased in four variants with single amino acid substitution. With another four variants having two amino acid substitutions involving combinations of the above single amino acid substitutions, the FXa-inhibitory activity was further increased. Because the electrostatic interaction within R-020-FXa complex seemed stronger in these R-020 variants, this increase in FXa-inhibitory effect was speculated to be a consequence of more potent binding between the enzyme and the inhibitor.

Production of IL-1 and its receptor antagonist is regulated differently by IFN-gamma and IL-4 in human monocytes and alveolar macrophages

Interleukin-4 (IL-4) has previously been found to downregulate interleukin-1 (IL-1) production, but to upregulate the production of IL-1 receptor antagonist (IL-1ra) in human monocytes stimulated with lipopolysaccharide (LPS). In the present study we wanted to determine whether the production of IL-1ra in human monocytes and alveolar macrophages (AMs) is regulated differently at the protein and messenger ribonucleic acid (mRNA) levels by IL-4 and interferon-gamma (IFN-gamma). AMs and monocytes obtained from healthy donors by bronchoalveolar lavage and centrifugal elutriation were stimulated with LPS in the presence or absence of IL-4 or IFN-gamma, and the expression of mRNA for IL-1 and IL-1ra was measured by Northern blot analysis. The production of IL-1 and IL-1ra was quantitated by enzyme immunoassays (EIAs). Spontaneous IL-1ra production was seen in AMs after incubation for 4 h in medium alone, but not in blood monocytes, at both the protein and mRNA levels. The spontaneous expression of the IL-1ra gene in AMs was augmented by incubation with IL-4. Interleukin-1 beta (IL-1 beta) production by LPS-stimulated AMs and monocytes was upregulated by IFN-gamma, but downregulated by IL-4. Interestingly, when stimulated with LPS, IFN-gamma inhibited IL-1ra production by monocytes, but up-regulated its production in human AMs at the protein and mRNA levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Novel factor Xa and plasma kallikrein inhibitory-activities of the second Kunitz-type inhibitory domain of urinary trypsin inhibitor

Urinary trypsin inhibitor is a glycoprotein with a structure in which two Kunitz-type inhibitory domains are linked in a row. We isolated two genes encoding the 70 amino acid sequence from the 78th amino acid (Thr) to the C-terminal and the 68 amino acid sequence from the 80th (Ala) to the C-terminal of human urinary trypsin inhibitor, both which correspond to the second Kunitz-type inhibitory domain, and then constructed expression plasmids by ligating it to the E. coli alkaline phosphatase signal peptide gene. These plasmids under the control of the tryptophan promoter expressed the second domain in E. coli strain JE5505 which lacks the membrane lipoprotein. The recombinant second domain purified from the culture supernatant of the transformant inhibited trypsin, plasmin, leukocyte elastase and chymotrypsin which are known to be inhibited by urinary trypsin inhibitor. In addition it inhibited blood coagulation factor Xa and plasma kallikrein in a concentration dependent and competitive manner, and significantly prolonged the plasma-based activated partial thromboplastin time (APTT). The truncated natural counterpart obtained by a limited degradation of human urinary trypsin inhibitor also revealed the identical inhibitory activities.

Autonomous expressions of cytokine genes by human lung cancer cells and their paracrine regulation

Cell-to-cell interaction between tumors and host inflammatory cells is important for the subsequent cancer progression or regression. We examined the expressions of mRNAs for various proinflammatory cytokines by nine human lung cancer cell lines and the influences of cytokines on their gene expressions. The cytokines used were interleukin 1 beta (IL-1 beta), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-alpha), granulocyte-macrophage colony stimulating factor (GM-CSF) and monocyte chemotactic and activating factor. Gene expressions of cytokines were measured by Northern blot analysis. Substantial expressions of cytokine genes were detected in several lung cancer cell lines such as RERF-LC-MS, RERF-LC-OK and VMRC-LCD, although the levels of expression of each cytokine varied in different cell lines. Four lung cancer cell lines (RERF-LC-MS, RERF-LC-OK, A549 and YO-88) were used to examine the effects of exogenous cytokines (IL-1 beta, TNF-alpha and GM-CSF) on cytokine gene expressions by the cells. TNF-alpha and IL-1 beta caused significant changes in the levels of mRNA expressions of certain cytokines. Moreover, on stimulation with TNF-alpha, RERF-LC-OK cells produced IL-6 extracellularly. These extensive differences in the levels of gene expressions and productions of cytokines could have profound effects on the interactions between human lung cancer cells and the corresponding host cells.

Effects of hepatic enzyme inducers and mitogens on experimental Tyzzer's disease in rats

We studied the effects of chemicals which induce liver enlargement and can induce hepatic protein synthesis on experimental Tyzzer's disease in rats. Plasma transaminase values were evaluated as an indicator of the severity of the disease. Chemicals used were phenobarbital sodium and 3-methylcholanthrene as hepatic enzyme inducers, and lead nitrate and ethylene dibromide as mitogens of hepatocytes. In rats non infected with Tyzzer's organism, liver weight in those treated with these chemicals was higher than that in rats without chemical treatment. Tyzzer's disease-infected rats treated with these chemicals showed higher plasma transaminase values and more severe histopathologic liver lesions than infected rats without chemical treatment. The results indicated that the growth of Tyzzer's organisms in hepatocytes was accelerated in the course of hepatocytic metabolic changes during liver enlargement, and that protein synthesized in the hepatocyte may play an important role in the nutritive requirements of the organism.

Augmentation by transferrin of IL-2-inducible killer activity and perforin production of human CD8+ T cells

The effects of human transferrin (Tf) on lymphokine (IL-2)-activated killer (LAK) induction from blood lymphocytes of healthy donors was examined. LAK cells were induced by 6-day incubation in medium with recombinant human IL-2 of lymphocytes, and their cytotoxic activity was assessed by measuring 51Cr release from NK-resistant Daudi cells. Tf alone did not induce any LAK activity, but in combination with IL-2, it augmented LAK induction dose- and time-dependently. This augmenting effect was completely abolished by pretreatment with anti-Tf antiserum. Tf augmented the proliferative response of lymphocytes to IL-2 and their expressions of receptors for IL-2 and Tf. CD8+ T cells were isolated from purified blood lymphocytes using antibody-bound magnetic beads. Addition of Tf to cultures of CD8+ cells resulted in significant augmentation of killer cell induction and perforin (PFP) production after 4 days stimulation with IL-2. These results indicate that Tf is important in generation of IL-2-inducible killer properties and PFP activity of human CD8+ T cells.

Tyzzer's disease complicated with distemper in a puppy

A Pomeranian puppy which died from diarrhea and nasal discharge showed catarrhal pneumonia, acute enteritis and focal liver necrosis. Slender bacilli were detected within ileal enterocytes and hepatocytes. A double infection with a distemper virus and Tyzzer's organism at a cellular level was seen within the ileal enterocytes.

Enhancement by monocytes of perforin production and its gene expression by human CD8+ T cells stimulated with interleukin-2

Pore‐forming protein (PFP) is an important effector molecule for cytotoxicity mediated by cytotoxic T cells and NK cells. In the present study, the effect of monocytes on PFP production by inter‐leukin‐2 (IL‐2)‐stimulated T lymphocytes was examined. Highly purified lymphocytes (>99%) and monocytes (> 90%) were isolated by centrifugal elutriation from peripheral blood of healthy donors, and, CD4+ and CD8+ cells were isolated from the purified lymphocytes by using antibody‐bound magnetic beads. PFP production was quantitated with a universal microspectrophotometer in combination with immunostaining using anti‐PFP antibody. Monocytes did not produce any PFP. High levels of PFP production were observed in CD8+ cells, but not CD4+ cells after incubation for 4 days with IL‐2. Addition of monocytes to cultures of CD8 + cells resulted in significant augmentation of PFP production after 3 days’ stimulation with IL‐2. Monokines (TNFα and IL‐6) caused a significant increase in PFP production by IL‐2‐stimulated CD8+ cells. Northern blot analysis revealed that the PFP mRNA level was enhanced by stimulation with IL‐2, and that addition of monocytes to cultures of CD8 + cells plus IL‐2 augmented their PFP mRNA expression. These observations suggest that monocytes are important in in situ regulation of the CD8 + T cell‐mediated cytotoxic response through production of PFP.

Induction of a 26-kDa membrane-form tumor necrosis factor (TNF)-alpha in human alveolar macrophages

The expressions of a membrane form of TNF (m-TNF) by human alveolar macrophages (AM) and autologous blood monocytes from healthy donors were examined. Upon lipopolysaccharide (LPS) stimulation, AM produced 26-kDa TNF-alpha on their cell surface. We designed a bioassay for measuring m-TNF in which macrophages were fixed with paraformaldehyde after stimulation for 18 h, then m-TNF activity was assessed as cytotoxicity of fixed macrophages on L929 cells. This assay was specific to m-TNF because: 1) no soluble factors were contributed to the cytotoxicity of fixed AM, 2) anti-TNF-alpha monoclonal antibody completely neutralized m-TNF activity, and 3) m-TNF activity was not altered after low-pH or high-salt treatment. On LPS stimulation, AM produced significant amounts of m-TNF earlier than TNF-alpha secretion. AM also expressed significant amounts of m-TNF when stimulated with other bacterial components and their derivatives. Interleukin (IL)-4 suppressed both m-TNF production and TNF-alpha secretion. p-Toluene-sulfonyl-L-arginine methyl ester (TAME) inhibited specifically TNF-alpha secretion and not m-TNF expression. Although blood monocytes produced small amounts of m-TNF, monocyte-derived macrophages showed enhanced m-TNF after cultivation with GM-CSF for 10 days. These findings indicate that m-TNF is expressed as a step in the TNF-alpha producing system, and suggest that m-TNF may play important roles in exhibition of macrophage function in situ.

[Induction of tumor cell killing by human alveolar macrophages and its regulation by IL-4]

The present study was undertaken to examine the effects of IL-4 on induction of cytotoxic killer activity and on production of antitumor mediators by human monocytes and alveolar macrophages (AM). The spontaneous tumoricidal activity of AM was slightly suppressed by IL-4. Addition of IL-4 to cultures of AM or monocytes with endotoxin resulted in dose-dependent suppression of their cytotoxic activity against A375 and its variant cells resistant to IL-1 and TNF-alpha. IL-4 inhibited the production of IL-1 and TNF-alpha by AM at the protein and mRNA levels. Oxygen radical production was also suppressed by treating AM with IL-4. IL-1 receptor antagonist (IL-1ra) was also produced by monocytes stimulated with LPS, but not with IL-4. Marked up-regulation by IL-4 of IL-1ra production in LPS-stimulated monocytes was observed at both the mRNA and protein levels. These findings suggest that IL-4 may be important in down-regulation of antitumor activation of human monocyte-macrophages, not only directly through inhibition of production of antitumor effector molecules, but also indirectly through up-regulation of production of IL-1ra.

Frozen-thawed human blood monocytes respond reproducibly to activation stimuli: implications for screening of BRMs

The purpose of this study was to identify the optimal freezing conditions for human blood monocytes to allow their recovery and use for in vitro screening of activation stimuli. Human monocytes separated from buffy coats of healthy blood donors were suspended at a density of 1 x 10(7) cells/ml in freezing medium consisting of 70% medium: 20% fetal bovine serum: 10% DMSO frozen in a stepdown freezer, and stored at -180 degrees C. Monocytes were thawed at different times up to 4 months later. Viability was > 90%. Fresh monocytes from different donors and frozen monocytes thawed at different times were incubated with different concentrations of lipopolysaccharide, muramyl tripeptide, muramyl dipeptide, or lipopeptide. Tumoricidal activity and IL-1 production of fresh monocytes varied greatly among the 5 different preparations. In contrast, the frozen monocytes (thawed at different times) produced uniform levels of antitumor activity and IL-1 production. These results show that monocytes recovered from frozen storage maintain their ability to respond to activation stimuli in a uniform and reproducible manner. Thus, the use of frozen-thawed monocytes is recommended for screening of macrophage-activating agents.

IL-4 up-regulates IL-1 receptor antagonist gene expression and its production in human blood monocytes

IL-4 down-regulates the productions of IL-1 and TNF-alpha in human monocytes. We examined whether the productions of IL-1 and a specific receptor antagonist of IL-1 (IL-1Ra) in human blood monocytes were regulated differently. Highly purified blood monocytes, isolated by centrifugal elutriation from healthy donors, were stimulated with LPS in the presence or absence of IL-4, and their productions of IL-1 and IL-1Ra were measured by Northern blot and immunoblot analyses. IL-1 and IL-1Ra were produced by monocytes stimulated with LPS, but not with IL-4 alone. Marked up-regulation by IL-4 of IL-1Ra production in LPS-stimulated monocytes was observed at both the mRNA and protein levels. Maximal expressions of IL-1 beta and IL-1Ra mRNA in LPS-stimulated monocytes were observed 2 h and 8 h, respectively, after stimulation. The enhancement of IL-1Ra production by IL-4 was concluded to be due to enhanced gene transcription, because there was no difference in the half-lives of IL-1Ra mRNA in monocytes cultured with and without IL-4. Up-regulation of IL-1Ra production by IL-4 was also observed in monocytes stimulated with adherent IgG at both the mRNA and protein levels. This unique property of IL-4 may be important in down-regulation of the IL-1-initiated immune and/or inflammatory response, not only directly through inhibition of IL-1 production, but also indirectly through up-regulation of IL-1Ra production.

IL-4 up-regulates IL-1 receptor antagonist gene expression and its production in human blood monocytes

IL-4 down-regulates the productions of IL-1 and TNF-alpha in human monocytes. We examined whether the productions of IL-1 and a specific receptor antagonist of IL-1 (IL-1Ra) in human blood monocytes were regulated differently. Highly purified blood monocytes, isolated by centrifugal elutriation from healthy donors, were stimulated with LPS in the presence or absence of IL-4, and their productions of IL-1 and IL-1Ra were measured by Northern blot and immunoblot analyses. IL-1 and IL-1Ra were produced by monocytes stimulated with LPS, but not with IL-4 alone. Marked up-regulation by IL-4 of IL-1Ra production in LPS-stimulated monocytes was observed at both the mRNA and protein levels. Maximal expressions of IL-1 beta and IL-1Ra mRNA in LPS-stimulated monocytes were observed 2 h and 8 h, respectively, after stimulation. The enhancement of IL-1Ra production by IL-4 was concluded to be due to enhanced gene transcription, because there was no difference in the half-lives of IL-1Ra mRNA in monocytes cultured with and without IL-4. Up-regulation of IL-1Ra production by IL-4 was also observed in monocytes stimulated with adherent IgG at both the mRNA and protein levels. This unique property of IL-4 may be important in down-regulation of the IL-1-initiated immune and/or inflammatory response, not only directly through inhibition of IL-1 production, but also indirectly through up-regulation of IL-1Ra production.

[Induction by local injections of IL-2 of antitumor effector cells and secondary production of cytokines in malignant pleural effusion]

The present study was undertaken to examine the effects of intrapleural administration of IL-2 on induction of cytotoxic killer cells and on secondary production of cytokines in malignant pleural effusions. During daily local administration of IL-2, significant in vivo induction of cytotoxic activity was observed after 3-7 days, followed by a decrease in this activity in pleural mononuclear cells (MNC) to almost zero by day 15. IL-4 suppressed induction of IL-2-inducible killer cells from MNC in blood and pleural effusion, but significantly augmented the killer induction from pleural effusion MNC obtained after local 7-day administration of IL-2. Before therapy, malignant pleural effusions contained various levels of IL-6 and M-CSF, but no IL-4 or IFN-gamma. Daily intrapleural instillation of IL-2 resulted in significant augmentation of the levels of IL-4, IL-6, IFN-gamma and M-CSF. Chromatographical fractionation of the pleural effusion showed only one major peak with a MW of 24 kD, which had IL-6 activity. The level of the latent form of TGF-beta also increased during local IL-2 therapy. In contrast, significant levels of TNF (alpha, beta), IL-1 beta or IFN-alpha were not detectable in pleural effusions before or during therapy. These data suggest that IL-2 is an important inducer of secondary production of various cytokines in vivo, responsible for up- or down-regulation of induction of IL-2-inducible killer activity.

Differential effects of interleukin-4 on superoxide anion production by human alveolar macrophages stimulated with lipopolysaccharide and interferon-gamma

The effect of interleukin-4 (IL-4) on the activation state of human alveolar macrophages (AMs) and blood monocytes induced by lipopolysaccharide (LPS) or recombinant interferon-gamma (IFN-gamma) was investigated on the basis of their ability to produce superoxide anion (O2-). AMs were obtained from healthy donors by bronchoalveolar lavage, and O2- productions of these cells were assayed by a cytochrome c reduction method after incubation with stimulants for 24 h. AMs produced more O2- than autologous blood monocytes when stimulated with LPS. IL-4 alone had little effect on O2- production by unstimulated AMs but down-regulated O2- production by LPS-stimulated AMs in a dose-dependent manner. IL-4 also suppressed O2- production by AMs induced by the synergistic actions of muramyl dipeptide (norMDP) and IFN-gamma. Maximum suppression by IL-4 of O2- production by AMs was observed when IL-4 was added within 1 h after initiation of LPS stimulation. AMs also showed high O2- production when stimulated with IFN-gamma alone. In contrast to its suppression of O2- production by LPS-stimulated AMs, IL-4 enhanced O2- production by AMs stimulated with IFN-gamma. These data suggest that IL-4 is an important regulator of O2- production by macrophages through different pathways depending on the stimulus.

IL-6 in malignant pleural effusions and its augmentation by intrapleural instillation of IL-2

The levels and activities of endogenous IL-6 in malignant pleural effusions due to lung cancer before and during daily intrapleural instillations of recombinant IL-2 were examined by enzyme immunoassay and bioassay using an IL-6-dependent murine hybridoma cell line MH60.BSF2. Before therapy, malignant pleural effusions contained various levels of IL-6. Daily intrapleural instillation of recombinant IL-2 for treatment of malignant pleurisy resulted in significant augmentation of the levels and activities of IL-6 in the pleural effusions. On fractionation of the pleural effusion by chromatography, one major peak of material with a mol. wt of 24 kD showed IL-6 activity. In contrast, no significant level of tumour necrosis factor-alpha or IL-1 beta was detectable in pleural effusions before or during local IL-2 therapy. These data suggest that IL-2 is an important regulatory factor of secondary IL-6 production.

Interleukin-4 as a potent down-regulator for human alveolar macrophages capable of producing tumour necrosis factor-alpha and interleukin-1

The effects of recombinant human interleukin-4 (IL-4) on the production of interleukin-1 (IL-1) and tumour necrosis factor-alpha (TNF alpha) by human alveolar macrophages (AM) and autologous peripheral blood monocytes (PBM) in response to lipopolysaccharide (LPS) were examined. AM and PBM were obtained by bronchoalveolar lavage and centrifugal elutriation, respectively, from healthy donors. The production of IL-1 (alpha and beta) and TNF alpha by human AM and PBM were quantitated by enzyme immunoassays (EIA). When activated with LPS, AM secreted much more TNF alpha, but less IL-1 beta than PBM. The production of IL-1 (alpha and beta) by activated AM and autologous PBM was suppressed dose-dependently by IL-4. The inhibitory effect of IL-4 was greatest when it was added to AM or PBM simultaneously with LPS or within 3 h after LPS. The suppressive effect of IL-4 was completely neutralized by pretreatment with rabbit anti-IL-4 antiserum. IL-4 also suppressed the production of IL-1 and TNF alpha by monocyte-derived macrophages. As measured by thymocyte co-stimulation assay, the production of cell-associated IL-1 was inhibited by coculture of AM plus LPS with IL-4. Northern blot analysis showed suppression by IL-4 of expression of messenger ribonucleic acid (mRNA) for IL-1 and TNF alpha in LPS-stimulated AM. We conclude that IL-4 is a potent down-regulator for human alveolar macrophages capable of producing IL-1 and TNF alpha.

Interleukin-4 as a potent down-regulator for human alveolar macrophages capable of producing tumour necrosis factor-alpha and interleukin-1

The effects of recombinant human interleukin-4 (IL-4) on the production of interleukin-1 (IL-1) and tumour necrosis factor-alpha (TNF alpha) by human alveolar macrophages (AM) and autologous peripheral blood monocytes (PBM) in response to lipopolysaccharide (LPS) were examined. AM and PBM were obtained by bronchoalveolar lavage and centrifugal elutriation, respectively, from healthy donors. The production of IL-1 (alpha and beta) and TNF alpha by human AM and PBM were quantitated by enzyme immunoassays (EIA). When activated with LPS, AM secreted much more TNF alpha, but less IL-1 beta than PBM. The production of IL-1 (alpha and beta) by activated AM and autologous PBM was suppressed dose-dependently by IL-4. The inhibitory effect of IL-4 was greatest when it was added to AM or PBM simultaneously with LPS or within 3 h after LPS. The suppressive effect of IL-4 was completely neutralized by pretreatment with rabbit anti-IL-4 antiserum. IL-4 also suppressed the production of IL-1 and TNF alpha by monocyte-derived macrophages. As measured by thymocyte co-stimulation assay, the production of cell-associated IL-1 was inhibited by coculture of AM plus LPS with IL-4. Northern blot analysis showed suppression by IL-4 of expression of messenger ribonucleic acid (mRNA) for IL-1 and TNF alpha in LPS-stimulated AM. We conclude that IL-4 is a potent down-regulator for human alveolar macrophages capable of producing IL-1 and TNF alpha.

Down-regulation by interleukin 4 of activation of human alveolar macrophages to the tumoricidal state

The effect of recombinant human interleukin 4 (IL-4) on the expression of antitumor activity of human alveolar macrophages (AM) obtained by bronchoalveolar lavage from healthy donors was examined. AM were incubated for 16 h in medium with various macrophage activators [lipopolysaccharide, des-methyl muramyldipeptide, Nocardia rubra cell wall skeleton, and heptanoyl-gamma-D-Glu-(L)-meso-alpha,epsilon-A2pm(L)-D-Al aOH] in the presence or absence of IL-4, and then their tumoricidal activity was assayed by measuring 125I-UdR release from human melanoma (A375) cells. The spontaneous tumoricidal activity of AM was slightly suppressed by IL-4 in 3 of 7 donors. Addition of IL-4 to cultures of AM with the activators resulted in dose-dependent suppression of AM-mediated cytotoxicity against A375 cells. IL-4 also inhibited AM-mediated cytotoxicity against A375-R cells, which are resistant to interleukin 1 (IL-1) and tumor necrosis factor alpha, HT-29 colon cancer cells, and KB cells. IL-4 inhibited the early induction phase of AM activation. Pretreatment of AM with IL-4 also suppressed their expression of antitumor activity in response to lipopolysaccharide. IL-4 inhibited the production of monokines (IL-1 and tumor necrosis factor alpha) by AM at the protein and mRNA levels. These findings suggest that IL-4 may be important in vivo in the down-regulation of antitumor expression of AM in the lung by inhibiting the production of monokines and other killing mechanisms.

Growth of Tyzzer's organisms in preneoplastic hepatocytes of rats

Tyzzer's disease in rats carrying preneoplastic or neoplastic lesions in the liver was studied histopathologically and immunohistochemically. The formation of necrotic foci and the growth of organisms were detected within both glutathione S-transferase placental type (GST-P) positive preneoplastic or neoplastic hepatocyte areas and GST-P negative areas. However, plasma glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) values and number of necrotic foci of infected animals having preneoplastic lesions in the liver were smaller than those of infected animals receiving no carcinogenic procedure. These results suggest that the environment consisted of preneoplastic hepatocytes was unsuitable for the growth of organisms as compared with that of intact hepatocytes though the organism could grow within the preneoplastic hepatocytes.

Optimization of the liposomes encapsulating a new lipopeptide CGP 31362 for efficient activation of tumoricidal properties in monocytes and macrophages

The purpose of this study was to optimize a suitable liposomal carrier for CGP 31362, a new synthetic lipopeptide analogue of gram-negative bacterial cell walls. CGP 31362 was inserted into the membranes of different liposomes with different phospholipid composition. We determined the ability of these liposomes to activate tumoricidal properties in mouse peritoneal and bone marrow macrophages, and in human monocytes. The ideal liposome carrier for CGP 31362 consisted of phosphatidylcholine and phosphatidylserine in a 7:3 molar ratio. Subsequent to efficient binding and endocytosis, CGP 31362 in liposomes of this composition rendered mouse macrophages and human monocytes highly tumoricidal. Moreover, even in the absence of interferon-gamma, human monocytes released significant levels of tumor necrosis factor and interleukin-1. These data show that in a suitable liposomal carrier, the new synthetic lipopeptide in liposomes is a potent activator of tumoricidal properties in macrophages.

Interleukin-2-inducible killer activity and its regulation by blood monocytes from autologous lymphocytes of lung cancer patients

The ability of blood lymphocytes of newly diagnosed lung cancer patients to respond to interleukin 2 (IL-2) to become IL-2-activated killer (LAK) cells and its regulation by autologous monocytes were examined. LAK activity was measured by 51Cr release assay. The abilities of lymphocytes among blood mononuclear cells (MNC) of subjects of different ages without malignancies to generate LAK activity against NK-cell resistant Daudi cells and lung adenocarcinoma (PC-9) cells were very similar. The LAK activity of blood MNC of lung cancer patients was also nearly the same as that of blood MNC of control subjects. There was no significant difference in IL-2-inducible LAK activity between MNC of patients with small cell lung cancer (SCLC) and those of patients with non-SCLC. Monocytes and lymphocytes were separated from blood MNC on a one-step Percoll gradient. Monocytes of lung cancer patients were found to augment in vitro induction of LAK activity by IL-2 of autologous blood lymphocytes. In contrast, endotoxin-stimulated monocytes suppressed LAK induction of autologous lymphocytes of cancer patients. These findings suggest that administration of IL-2 and LAK cells induced in vitro may be of benefit in the treatment of lung cancer.

Cytotoxic potential of liposomes containing tumor necrosis factor-alpha against sensitive and resistant target cells

The purpose of these studies was to determine whether recombinant tumor necrosis factor (TNF) incorporated into liposomes produced enhanced antitumor effects against TNF-sensitive and TNF-resistant target cells. The lipid composition of liposomes influenced their binding to and endocytosis by target cells. Liposomes consisting of phosphatidylcholine and phosphatidylserine (7:3 molar ratio) bound to L929 cells and A375 human melanoma cells, albeit to different degrees. Liposomes retained encapsulated TNF for up to 48 h of incubation. TNF in liposomes lysed the TNF-sensitive A375 melanoma and L929 cells at levels similar to that mediated by free, unencapsulated TNF. Cells selected for resistance against free TNF were not sensitive to TNF in liposomes. Since liposomes concentrate in organs with high levels of reticuloendothelial activity, and TNF in liposomes retains antitumor activity, this delivery system may prove to be useful for treatment of lymph node and hepatic metastases.

Comparative efficacy of liposomes containing synthetic bacterial cell wall analogues for tumoricidal activation of monocytes and macrophages

We examined the activation to the tumoricidal state of normal mouse peritoneal exudate macrophages, bone marrow macrophages, and human blood monocytes by liposomes containing either lipophilic muramyl tripeptide (CGP 19,835) or a new synthetic analogue of lipoprotein from gram-negative bacteria outer wall, CGP 31,362, or combinations of the two. The superiority of liposomes containing the synthetic lipopeptide over liposomes containing lipophilic muramyl tripeptide for in vitro activation of monocytes and macrophages was demonstrated in several experiments. First, liposome-CGP-19,835 activated monocytes only in the presence of interferon-gamma, whereas activation with liposome-CGP 31,362 was interferon-independent. Second, activation of both mouse macrophages and human blood monocytes by liposome-CGP 31,362 occurred at a lower liposomal concentration than that by liposome-CGP 19,835. Third, monocytes incubated with liposome-CGP 31,362 released both tumor necrosis factor (TNF) and interleukin-1 activities, whereas monocytes treated with liposome-CGP 19,835 (in the absence of interferon-gamma) released only TNF activity. These data suggest that liposomes containing the synthetic lipopeptide CGP 31,362 are superior to liposomes containing CGP 19,835 for systemic activation of macrophages.

[Eosinophil colony stimulating activity induced by administration of interleukin-2 into the pleural cavity of patients with malignant pleurisy]

Systemic administration of interleukin-2 (IL-2) in patients with malignant diseases induces peripheral eosinophilia. In the present study, to clarify the mechanisms of eosinophilia induced by IL-2, we examined the changes in the number of eosinophils and in eosinophil colony stimulating activity (Eo-CSA) in the pleural fluid of six patients with malignant pleurisy caused by lung cancer or malignant mesothelioma, during and after intrapleural administration of IL-2. Results showed that intrapleural administration of IL-2 induced marked eosinophilia in the pleural fluid and mild eosinophilia in the peripheral blood, and that during IL-2 administration, marked Eo-CSA appeared in the pleural fluid before increase in the number of eosinophils. The Eo-CSA seemed to be a polypeptide or protein because it was trypsin-sensitive and had a molecular weight of 40-60 kDa.

Lymphokine-activated killer induction and its regulation by macrophages in malignant pleural effusions

Mononuclear cells (MNC) from pleural effusions and peripheral blood of 18 patients with primary lung cancer with malignant pleural effusion were studied. Pleural and blood MNC generated lymphokine-activated killer (LAK) activity similarly when cultured for 4 days with an optimal concentration of interleukin 2 (IL-2). Highly purified lymphocytes (greater than 98%) and monocyte-macrophages (greater than 90%) were isolated by discontinuous Percoll gradient centrifugation from pleural and blood MNC. Pleural macrophages, as well as blood monocytes, showed significant augmenting effects on in vitro LAK cell induction from pleural and blood lymphocytes by IL-2. During daily intrapleural administration of IL-2, significant induction of LAK activity in vivo was observed after 3 days, but then this LAK activity in pleural MNC decreased almost to zero by day 15. Daily injections of IL-2 resulted in reduction in the up-regulation of LAK induction by pleural macrophages and also in increases in the levels of soluble IL-2 receptors in pleural effusions. These findings indicate that in vivo LAK induction of lymphocytes in malignant effusions by IL-2 may be regulated by macrophages in the effusions.

Treatment of malignant ascites with allogeneic and autologous lymphokine-activated killer cells

Two cases of peritonitis carcinomatosa with gynecological cancer, which did not respond to conventional treatment, were treated by intraperitoneal adoptive immunotherapy with allogeneic or autologous lymphokine-activated killer (LAK) cells plus interleukin-2. In case 1, reduction of acute ascites and disappearance of malignant cells from the peritoneal fluid and decreased levels of tumor markers (CA12-5 and CA19-9) were demonstrated during the treatment. In case 2, which also received additional treatment for pleuritis carcinomatosa, reduction of ascites and pleural effusion and disappearance of malignant cells from the pleural fluid were noted. In these cases allogeneic LAK therapy was well tolerated. This therapy did not prolong the patients' lives, but the findings indicate that it had appreciable local antitumor effects on peritonitis and pleuritis carcinomatosa in these patients with gynecological cancer.

Heterogeneity of human lymphokine (IL-2)-activated killer (LAK) precursors and regulation of their LAK induction by blood monocytes

Highly purified lymphocytes (greater than 99%) and monocytes (greater than 90%) were isolated by CCE from peripheral blood of healthy donors. Blood lymphocytes were separated by this CCE into 9 subpopulations. The NK activities of these lymphocyte fractions against NK-sensitive K-562 cells and their LAK activities against NK cell-resistant target (Daudi) cells were assayed promptly or after incubation of the fractions for 4 days with or without an optimal concentration of IL-2. NK and LAK activities were measured by 4-hr 51Cr-release assay. On the basis of their NK and LAK activities, these lymphocyte fractions were classified into 3 subpopulations of LAK precursors: one lacking both NK and LAK activities (Fr.2), one with moderate NK activity but low LAK activity (Fr.5), and one possessing both NK and LAK activities (Fr.8). Addition of autologous fresh monocytes to the lymphocyte cultures resulted in a significant increase in induction of LAK activity in Fr.2 and Fr.5. This up-regulation of lymphocytes in Fr. 2 and Fr.5 by monocytes was confirmed in parallel experiments by measuring the blastogenic response of the lymphocytes to IL-2. Deletion of lymphocytes in Fr. 8 of CD16+ (Leu-11+) NK cells resulted in 74% reduction in LAK induction, whereas depletion of mixtures of monocytes and lymphocytes in Fr. 2 of cells reacting with CD3+ (OKT3+) antibody resulted in a 66% reduction in LAK induction. This up-regulation of LAK cell induction from LAK precursors by monocytes was confirmed using 4 lines of human lung cancer cells as targets for LAK activity. These results clearly indicate that human monocytes may cause up-regulation of the expression of IL-2-induced LAK activity in T cells and in a subpopulation of NK cells.

Expression and excretion of human pancreatic secretory trypsin inhibitor in lipoprotein-deletion mutant of Escherichia coli

We constructed a gene coding for the 56-amino acid human pancreatic secretory trypsin inhibitor (PSTI), and ligated it on a plasmid downstream from the trp promoter and the signal peptide sequence of alkaline phosphatase. The resulting plasmid was transfected into a lipoprotein deletion mutant (Escherichia coli JE5505) and the plasmid-carrying cells were induced with 3-indoleacrylic acid. A considerable amount (50 micrograms/ml culture) of the mature PSTI protein was detected in the culture supernatant. The excreted PSTI was identical to the natural PSTI protein with respect to the trypsin-inhibiting activity, the N-terminal and the C-terminal amino acid sequences and the amino acid composition.

Differential effects of recombinant interferons alpha, beta, and gamma on induction of human lymphokine (IL-2)-activated killer activity

The effects of three classes of recombinant interferons (IFN-alpha A, IFN-beta, and IFN-gamma) on maximal induction of lymphokine (IL-2)-activated killer (LAK) activity were studied. Highly purified lymphocytes (greater than 99%) were obtained by counter-flow centrifugal elutriation from peripheral blood of healthy donors. After incubation for 4 days with IL-2 (1 U/ml), purified lymphocytes showed maximal LAK activity against NK cell-resistant target (Daudi) cells, as assessed by 4-hour 51Cr release assay. Addition of exogenous IFN-alpha A or IFN-beta to cultures of lymphocytes plus IL-2 resulted in significant inhibition of LAK activity, but addition of IFN-gamma had no effect on LAK induction by IL-2. IFN-alpha A caused greatest inhibition of LAK activity when added at the start of culture of lymphocytes with IL-2, and was less inhibitory when added 1 day later. Similar inhibition by IFN-alpha A or IFN-beta was observed with nine lines of human tumorigenic cells as targets of LAK activity. IFN-alpha A and IFN-beta also inhibited the proliferative responses of lymphocytes to IL-2 stimulation, and the expression of IL-2 receptors on their surface, whereas IFN-gamma did not. These results suggest that IFN-alpha A and IFN-beta may be important in in situ regulation of LAK cell induction against neoplasms.

Up- and down-regulation of human lymphokine (IL-2)-activated killer cell induction by monocytes, depending on their functional state

Studies were made to determine whether freshly isolated monocytes from healthy donors could influence the induction of lymphokine (IL-2)-activated killer (LAK) activity. Highly purified lymphocytes (greater than 99%) and monocytes (greater than 90%) were isolated by counter-flow centrifugal elutriation from peripheral blood. Lymphocytes incubated for 4 days with IL-2 showed significant LAK activity against natural killer (NK) cell-resistant target (Daudi) cells, whereas monocytes treated for 4 days with IL-2 and/or IFN-gamma were not cytotoxic. Under the experimental conditions used, addition of monocytes to the lymphocyte cultures resulted in significant augmentation of the LAK activity, depending on the density of monocytes added. In contrast, monocytes stimulated by lipopolysaccharide (LPS) markedly suppressed LAK activity induced by IL-2, depending on the dose of LPS added. Similar up- and down-regulations of LAK cell induction by monocytes were observed with 4 lines of human lung cancer cells as targets for LAK activity. Although supernatants from untreated monocytes did not increase LAK induction, supernatants from LPS-stimulated monocytes suppressed LAK induction. The regulatory role of monocytes could not be replaced by the addition of exogenous interleukin I (IL-I) or tumor necrosis factor (TNF). Prostaglandin E did not seem to play a regulatory role, since addition of indomethacin did not affect the regulation of LAK cell induction by monocytes. These results clearly indicate that human monocytes may cause up- or down-regulation of the expression of IL-2-induced LAK activity, depending on their functional state.

Synergism of synthetic acyltripeptide and its analogs with recombinant interferon gamma for activation of antitumor properties of human blood monocytes

Human blood monocytes freshly isolated by centrifugal elutriation from healthy volunteers were not cytotoxic to allogeneic A375 melanoma cells, but they were activated to the tumoricidal state by incubation in vitro with FK-565, (heptanoyl-gamma-D-Glu-(L)-meso-alpha,epsilon-A2pm(L)-D-A laOH), which is a synthetic acyltripeptide closely resembling cell wall peptidoglycan peptides of Streptomyces in structure. Among 11 different derivatives of FK-565, 7 analogs were more potent activators of monocytes for tumor cell killing than FK-565. The maximal expression of tumoricidal monocytes was dependent on the concentration of FK-565 or its analogs added and the ratio of monocytes to target tumor cells. In a parallel experiment, a combination of a subthreshold concentration of FK-565 or its analogs (FR-42148 and FR-42149) and recombinant interferon gamma (rIFN-gamma) induced significant monocyte-mediated tumorcell killing, indicating that the effects of rIFN-gamma and acyltripeptide or its analogs in monocyte activation are synergistic. In contrast to rIFN-gamma, recombinant rIFN-alpha A and rIFN-beta had additive effects with acyltripeptide or its analogs in human monocyte activation. These results suggested that synthetic acyltripeptide and its analogs combined with rIFN-gamma could be of clinical value for in situ activation of the tumoricidal activity of human blood monocytes responsible for eradication of cancer metastases.

Effects of human alveolar macrophages on the induction of lymphokine (IL 2)-activated killer cells

Normal human alveolar macrophages (AM) significantly and reproducibly suppress induction of IL 2-activated killer (LAK) cell activity against allogeneic Burkitt's lymphoma (Daudi) cells. Incubation of purified peripheral blood lymphocytes for 4 days with autologous AM and 1 U/ml of IL 2 resulted in AM-mediated suppression of LAK activity, whereas peripheral blood monocytes isolated freshly by centrifugal elutriation from the same donor potentiated induction of LAK activity by IL 2. The suppression of LAK cell induction by human AM was dependent on the density of AM added to the lymphocyte cultures. Recombinant IFN-gamma did not affect AM-mediated suppression of LAK cell induction by IL 2. Both AM and monocytes stimulated with lipopolysaccharide markedly suppressed LAK cell induction by IL 2. AM-mediated down-regulation was seen only when AM were added immediately after the start of incubation of lymphocytes with IL 2; AM potentiated LAK activity when added 1 day later. Similar AM-mediated suppression of LAK cell induction was observed with four lines of allogeneic lung cancer cells as targets for LAK activity. These results indicate that AM may be important in regulation of in situ induction of LAK activity in the lung.

Effects of human alveolar macrophages on the induction of lymphokine (IL 2)-activated killer cells

Normal human alveolar macrophages (AM) significantly and reproducibly suppress induction of IL 2-activated killer (LAK) cell activity against allogeneic Burkitt's lymphoma (Daudi) cells. Incubation of purified peripheral blood lymphocytes for 4 days with autologous AM and 1 U/ml of IL 2 resulted in AM-mediated suppression of LAK activity, whereas peripheral blood monocytes isolated freshly by centrifugal elutriation from the same donor potentiated induction of LAK activity by IL 2. The suppression of LAK cell induction by human AM was dependent on the density of AM added to the lymphocyte cultures. Recombinant IFN-gamma did not affect AM-mediated suppression of LAK cell induction by IL 2. Both AM and monocytes stimulated with lipopolysaccharide markedly suppressed LAK cell induction by IL 2. AM-mediated down-regulation was seen only when AM were added immediately after the start of incubation of lymphocytes with IL 2; AM potentiated LAK activity when added 1 day later. Similar AM-mediated suppression of LAK cell induction was observed with four lines of allogeneic lung cancer cells as targets for LAK activity. These results indicate that AM may be important in regulation of in situ induction of LAK activity in the lung.

[Lymphokine-activated killer (LAK) adoptive immunotherapy: optimal method for large-scale LAK induction]

Adoptive immunotherapy with lymphokine-activated killer (LAK) cells shows promise as a treatment for malignant disease, but one of the difficult problems associated with the LAK therapy is the method to induce 10(11) to 10(12) of LAK cells. In a study for optimal LAK induction, monocytes separated with counterflow centrifugal elutriation markedly augmented LAK cell induction from lymphocytes in spite of having no cytotoxicity when cultured alone; LAK activity was sufficiently induced from mononuclear cells (MNC) containing approximately 20% of monocytes; LAK activity was induced depending on the serum concentration, and at least 5% of human AB serum in RPMI 1640 was referred to induce optimal LAK activity; and roller bottle was preferable to tube or flask especially at higher MNC density. We concluded that roller bottle with 4 X 10(6) cells/ml of MNC suspended in 1 liter of RPMI 1640 containing 5% AB serum would be the optimal condition for large-scale LAK induction, and administration of LAK cells on the 3rd and 4th day of culture is favorable for weekly performance of LAK adoptive therapy.

The steroid binding domain of porcine estrogen receptor

For the purpose of characterizing the estrogen binding domain of porcine estrogen receptor (ER), we have made use of affinity labeling of partially purified ER with [3H]tamoxifen aziridine. The labeling is very efficient and selective particularly after partial purification of ER. A 65,000-dalton (65-kDa) band was detected on the fluorogram of a sodium dodecyl sulfate-polyacrylamide gel, together with a 50-kDa band and a few more smaller bands. The 50-kDa protein appears to be a degradation product of the 65-kDa protein in view of the similar peptide map. ER was affinity labeled before or after controlled limited proteolysis with either trypsin, papain, or alpha-chymotrypsin. The labeling patterns of limited digests indicate that a fragment of about 30 kDa is relatively resistant to proteases and has a full and specific binding activity to estrogen, whereas smaller fragments have lost much of the binding activity. This fragment is very hydrophobic and probably corresponds to the carboxy half of ER.